A population-based study was performed in Western Australia, identifying children with cerebral palsy born in the 1980s and linking information on plurality ascertained through vital statistics of the Health Department of Western Australia. This work confirmed earlier findings from the NEB and extended them to include triplets. The chance that a triplet pregnancy will produce a child with cerebral palsy is 47 times greater than for a singleton pregnancy. An International Collaborative Study of Childhood Neurologic Disorders in Multiple Births has begun. A colleague from Western Australia will come to the NEB for six months to work on the study.